Star, sadly I agree with Agnes.
I am convinced that the only reason we won our case so (ha!) easily is that we had let dd1 fail in a series of settings.
So, she failed in ms pre-school, with all the usual key worker, extra funding crap.
Then she failed in a specialist asd preschool, with a class size of 10, with a SALT,asd teacher and trained TA per class.
During her time at specialist asd preschool we were mostly noy running our home.programme, due to lack of tutors, but it certain.pt gave them enough rope to hang themselves.
We re started ABA, and within 3 days dd1 was talking more amd interacting more at school. School tried to say it was because she was npw settled, but it was a) the first week back after summer break, b) a new class and teacher for dd1, and c) the onpy staff member who she had interested with the previous year was no longer there (with no explanation or preparation given to dd1)
So, we simultaneously proved no progress without ABA, instant progress with ABA, and generalization from ABA programme without that actually being a target.
But we had to let her fail across settinhgs, proving that even the gold standard LA interventions (this was a place that patents take LA to tribunal to get INTO) would fail dd1, akd that the LA had nothing else to ofer.
It is depressing.g, but true. You have to give it a reasonable length of time, otherwise you will be deemed to have not tried it fully. and it is disgusting that this is the system we face - where we have to let our children fail in order to prove a point, but it is what it is.
it is a marathon, not a sprint. It feels like forever now, but it will enable you to get better provision, for longer, for your ds.